I worked on the project from its beginnings in 2006 up through 2010
when I decided to move on to other projects. I wrote the majority of
the code in the first version of the
server, and I've been involved
with almost every aspect of the project, including documentation (I
wrote big chunks of the user and developer manuals), consultancy, and
giving talks at various venues explaining various aspects of the
system.

Besides the core code, I've also written a number of extensions to the
system:

The AMQP specification

I've also contributed to the AMQP specification development process:
RabbitMQ is a member of the AMQP working
group. I've
personally spent time working on AMQP's session management, batch
acknowledgement protocols, transactional protocols, and on-the-wire
binary message formatting.